<?php

abstract AB
{
    public function run()
    {
        echo 'running...';
    }

    abstract public function eat();
    abstract public function sleep();
}

class Test extends AB
{
    public function eat()
    {
        echo 'eating...';
    }

    public function sleep()
    {
        echo 'sleeping...';
    }
}

$test = new Test();
$test->eat();